Terminal bushing



April 20, 1937. R, GQBER 2,077,686

TERMINAL BUSHING Filed Nov. 30, 1935 INVENTOR ATTORN EY Patented Apr.20, 1937 UNITED STATES PATENT OFFICE 2 Claims.

, This invention relates to means'for mounting devices, such as electricterminals or lamps, in surfaces, such as electrical display signs.

It is an object of the invention to provide a unitary device of thecharacter described which may be instantly attached or detached.

Another object of the invention is to provide a receptacle supporterwhich when an object is mounted therein, will prevent the entrance ofmoisture past the receptacle.

Still another object of the invention is to provide a supporter, for areceptacle mountable in apertures in a plate having an enamelledsurface, which will not chip or check the enamel of said surface.

A further object of the invention is to provide a supporter, for areceptacle mountable in an aperture in a plate, which will accommodateitself to variations in size and shape of said aperture.

The invention possesses other objects, and valuable features, some ofwhich, together with the foregoing, will be specifically set forth inthe specification hereunto annexed. It is. to be understood that theinvention is not to be limited to that 25 form thereof shown anddescribed as various other embodiments thereof may be employed withinthe scope of the appended claims.

Referring to the drawing:

Figure 1 is a rear elevational view, of the receptacle and the supportertherefor, mounted in a section of sheet material. A portion of the viewis broken away and shown in section to more clearly disclose theconstruction.

. Figure 2 is aview, partly in side elevation and partly in verticalsection, of the receptacle and supporter. The planes, in which the viewis taken, are indicated by the line 2-2 of Figure 1.

In detail, my invention. finds its greatest use in electrical displaysigns which are provided with a plate 3 having an aperture 4 therein.These apertures are provided in a surface of the sign throughwhichelectrical conductors are led to supply current to the sign lamps,or, in the case of signs equipped with gas -filled electric dischargetubes, to provide anchors for the terminals of the tubes. The usualprocedure is to insert in each aperture, from each side of the plate,mating halves of, usuallyporcelain bushings, which bushings are usuallyjoined together by means of screw 50 threads. In the signs, in which theplate is enameled, over-tightening of the sections of the bushings willcrack or check the enamel, thereby allowing the entry of water to themetal which will quickly corrode the latter and cause destruc- 55 tionof the bond between the enamel and the underlying plate. To prevent thepossibility of so cracking the enamel, it is the usual practice toprovide rubber gaskets, between the bushing sections and the plate,which will absorb any excess pressure created by overtightening of thesections.

The life of these gaskets is, however, very short, due to the smallamount of rubber therein which will, after exposure to the elements fora-short time, lose its elasticity and possibly develop cracks whichcracks will admit moisture to seep through the plate and upon reachingbare current-carrying terminals or conductors cause leakage of thecurrent to ground which is often of such an amount as to blow the linefuses. The porcelain bushing members are also subject to cracking, dueto excess vibration, which will cause further entry of water through theplate. Another undesirable feature is that should a porcelain section ofthe bushing become cracked it will be usually found that upon removalthereof, the rubber gasket has adhered to both the bushing and platewith the result that when the bushing is removed, the gasket will bedestroyed, necessitating its replacement. If the section of the bushingwithin the sign becomes damaged, it is obvious that consider= able workis necessary to replace it since it may be reached only from the rear ofthe sign. This type of replacement usually requires the services of twomen, respectively, in front and at the rear of the sign so that the twosections of the bushing may be properly mounted.

I have overcome all of these difliculties by providing a bushing whichis constructed as a unit, which may be instantly attached or detached,which will provide a water-tight connection, thereby preventing thepassage of moisture through the plate with which it is used, and whichwill act, in signs provided with frail glass tubes, as a shock absorberfor protecting the tubes against excessive vibration.

The bushing comprises a rubber annulus having a central bore 5 and agroove 6 in the periphery thereof which provides a head portion,generally indicated by the numeral i, and a skirt portion indicated bythe numeral ii. The head is cut, as is shown in Figure l, to provide arim 9, which receives the U-shaped flange iii of a metallic socketprovided with a sleeve I I, positioned in the bore 5, and having screwthreads formed therein which engage corresponding threads formed on aterminal plug indicated by the dot and dash lines l2, and a flap i3which overlies the flange I0 and provides a gasket it between the flangeand the flange l5 formed on the terminal plug.

ture, the former is tilted and a portion of theskirtlisinsertedintheaperturesothatthe edge of the aperture will beseatedin the groove 8. The bushing is now pressed axially of theaperture and, at the same time, forced transversely thereof, toward thepoint of engagement of the plate withthe groove, so that the outer edgeof the skirt at the top of the groove will be brought into alinementwith the edged the plate aperture whereupon the skirt may be pushedthrough the aperture and allowed to expan'dsothat the platewillbeseatedinthe groove 6.

In detaching the bushing, it will be apparent that by bending a portionof the skirt 8 inwardly toward the axis of the bore 5, and pushing thebent portion/of the skirt through the plate aperture, the remainder ofthe skirt will follow through the aperture upon exerting a slight pullon the bushing axially thereof.

Upon inspection of Figure 2'it will be seen that when the bushing is inplace in the plate aperture, and the flange ii of is screwed intocontact with the gasket portion ll of the head of the bushing, allpoints through which water might pass through the plate aperture aresealed, thus assuring, regardless of the quantity of water on thesurface of the plate or the force of wind against the surface whichwould quickly drive water through any aperture in the plate if thelatter existed, that the current carrying elementsv within the sign areprotected against possible leakage or short circuiting.

It will also be apparent the bushing provides a resilient mounting, forelectric discharge tubesjwhich will protect the latter against abnormalshocks or vibration and thereby prevent 40 cracking or shattering of thefragile glass tubing thereof.

the terminal plug 2,077,886 In mounting the bushing in the plate aper-Other important features are that the bushing is a unitary structurewhich requires the use of no separate washers or other such parts in theattachment thereof; that, comprising but a single piece it may bemounted and dismounted by one man, and, when the knack of insert ing itin the plate aperture has been mastered. by the use of but one hand; anddue to the absence of am; unyielding surfaces for securing the bushingin the plate aperture, the danger of chipping or cracking of the surfaceof the plate, should the latter be enameled, is eliminated.

What is claimed is:

1. An electrical terminal bushing adapted to be inserted in a platehaving an aperture therein, comprising an annulus of resilient materialhaving a peripheral groove therein, a portion lying at one side of saidgroove deformable to pass through said aperture to position said groovein engagement with portions of said plate bordering said aperture, aportion lying at the other side of said groove, and a terminal receivingmember having a flange thereon embedded in said last mentioned portionof said annulus.

2. An electrical terminal bushing adapted to be inserted in a platehaving an aperture therein, comprising a ring of resilient materialhaving a peripheral groove to provide a pair of spaced rims, one of saidrims being deformable to pass through said aperture to position saidgroove in engagement with portions of said plate bordering saidaperture, a terminal receiving socket disposed in said ring and having aflange secured to said other rim, and an integral portion of said otherrim overlying said flange to provide a gasket between said flange and asurface of an element carrying an electric terminal inserted in saidsocket.

GEORGE R. GOBER.

